Thermal imaging combination and method

ABSTRACT

A thermal imaging instrument and method is disclosed for viewing hot spots within a normally enclosed cabinet, for example, a high voltage electrical power distribution cabinet. Large and expensive thermal viewing windows normally required for thermal examination of these cabinets utilizing standard thermal imaging cameras is obviated by the use of an accessory lens assembly. The unique combination and methodology of using the lens assembly, standard thermal imaging camera and small access opening in the cabinet face allows for the retention of the safety rating of the cabinet. Further adding to the accuracy, convenience and safety of the approach, an infrared view port, together with cap and ring chain assembly, is permanently affixed to the cabinet face in relation to the small access hole.  
     The unique combination of the instrument portion of the invention can be integrally combined in a single unit for exclusive use in detecting hot spots within a cabinet.

[0001] This invention claims the benefit of U.S. Provisional ApplicationNo. 60/362,743, filed Mar. 8, 2002. This invention relates generally toa thermal imaging combination and method for measuring hot spots.

BACKGROUND

[0002] Specifically the invention includes an assembly combination andmethodology for monitoring the thermal profile of an interior panel of ashut cabinet, for example, a power distribution box.

[0003] There are important applications in electrical power distributionthat involve measurement of hot spots within electrical high voltagecabinets without compromising the safety of working personnel. One wayis to open the cabinet door and make a quick thermal image of electricalpanel. However, for a high voltage electrical cabinet, the door of thecabinet can only be opened if the power is first shut-off. As a safetyprecaution, the cabinet door is interlocked with the incoming powercircuit breaker. The fact the power is turned off results in a coolingof electrical circuit breakers. This can result in the rapidredistribution of accumulated heat, precluding the identifications ofthe true hot spots. Also shutting off the power may not be desirable tothe operation of down stream users.

[0004] An alternative, albeit expensive, method employed today involvesinstalling one or more infrared transmitting windows in the cabinetdoor. This allows the direct thermal “viewing” of the interior of anelectrical panel, without opening the cabinet door. The diameter ofthese windows is large in order to accommodate the large aperture of athermal imaging camera's objective lens. The typical window diameter is3″ (75 mm). To maintain the NEMA (National Electrical ManufacturingAssociation) safety rating, such as 1, 2, 3, 4, or 12, of the cabinet,qualified personnel should perform the installation of this window(s);or they should be installed at the time the electrical cabinet isassembled. This involves the customization of the electrical cabinet. Itis to these problems that the present invention is directed.

[0005] It is therefore a primary object of the present invention toprovide a method and means for evaluating the thermal profile of theinterior of an enclosure without degrading the integrity of theenclosure.

[0006] It is still another object of the present invention to provide amethod and means for evaluating the thermal profile of the interior ofthe enclosure without opening any access door.

[0007] It is yet another object of the present invention to expand thebreadth of applications for thermal imaging equipment by facilitatingtheir use with enclosures containing heat generating equipment whichneeds to be monitored.

[0008] Still another object is to provide a means and method forsurveying a broad internal area of an enclosure, again without violatingthe integrity thereof or accessing the interior through the opening ofan enclosure door.

[0009] A still further object is to provide a means and method formaking accurate thermal profiles of the interior of an enclosure eventhough the heat source within the enclosure may be positioned at variousdepths from the evaluating means.

SUMMARY

[0010] These and other objects are obtained with the thermal imagingcombination and method of the present invention. It occurred to theapplicant that an innovative lens assembly design (designated a“fisheye” assembly by the applicant) could simplify this costly anddifficult measurement. Rather than placing a large diameter window(s) inthe face of the cabinet door, a ⅝″ (16 mm) hole is drilled in the centerof the cabinet door. A ⅝″ hole is permitted without compromising thesafety issues. The hole can be effectively sealed while not in use. Assuch, the door is still able to maintain its NEMA rating. The fisheyelens assembly with a 66° diagonally wide angle field of view, can imagea broad section of the cabinet interior for hot spots through this hole,in one exercise. The small objective lens of the fisheye assemblyprovides very wide angle viewing, at different depths, withoutcompromising the quality of the received thermal image and the NEDT(Noise Equivalent Differential temperature) of the thermal imagingsystem.

[0011] In the preferred embodiment the design of the fisheye lensassembly includes multi-element, infrared transmitting optical materialconsistent with the spectral transmission characteristics of the thermalimager camera, for example, Model #s 7102, 7200 and 7515, manufacturedby Mikron Instrument Company, Inc. of Oakland, N.J., (hereinafter“Mikron”), connected to the fisheye assembly. The lenses are placedinside a precision housing with appropriate spacing between the variouslenses. A mechanism for manual focusing allows the best image qualityfor various depths of field, typically between 4″ to 45″ distance.Therefore the user has the advantage of expanding the capabilities ofthe thermal imager, to cover practically all preventative maintenanceapplications.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012]FIG. 1 is a perspective view of one version of the combinationthermal camera-fisheye lens assembly portion of the present invention.

[0013]FIG. 2 is a perspective view of an operator using one version ofthe thermal camera-fisheye lens assembly-access hole combination of theinvention.

[0014]FIG. 3 is a partially sectional view of one version of thecombination thermal camera-fisheye lens assembly portion of the presentinvention.

[0015]FIG. 4 is a schematic representation of the lensing systememployed in one version of the fisheye lens assembly of the invention.

[0016]FIG. 5A is a front, elevation view of the nose portion of oneversion of the fisheye lens assembly of the invention.

[0017]FIG. 5B is a side, elevation view of the nose portion of oneversion of the invention similar to the view of FIG. 5A.

[0018]FIG. 5C is a side, sectional view of the nose portion of oneversion of the invention, taken along the lines 5C-5C of FIG. 5A.

[0019]FIG. 6 is a perspective view of a portion of the cabinet faceincluding the access opening portion of the present invention requiredfor thermal viewing of a shut cabinet and including an exploded view ofone version of a safety closure for the opening.

[0020]FIG. 7 is a side, elevation, partially sectional view of a shutcabinet in the process of being thermally examined by one version of thecombination thermal camera-fisheye lens assembly portion of theinvention.

[0021]FIG. 7A is a schematic representation of a typical area of a shutcabinet accessible to thermal viewing by one version of the combinationof the invention.

[0022]FIG. 8 is a graphic representation of a typical radiometricthermal image of a desired target produced by the thermal cameracomponent of the combination of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Turning now to the drawings, in FIG. 1 a version of the thermalimaging instrument portion 10 of the invention is depicted. Theinstrument 10 is a combination of a standard thermal imager camera 14(such as the Mikron model no. 7102, 7200, or 7515, and similar cameras),and a lens assembly 12, designated as a fisheye lens assembly 12.

[0024]FIG. 2 illustrates an operator 18 utilizing the combination of thethermal imaging camera 14 and fisheye lens assembly 12, making use ofthe strap 16 on the camera and the opening 92 in a cabinet closure 74 toview the interior of the cabinet for hot spots. The fisheye lensassembly 12 permits the use of thermal imagining cameras to see hotspots occurring over a relatively large area through a small accessopening. Means are disclosed hereinafter for effectively sealing theopening so as to not violate the electrical rating of the cabinet.

[0025] As best seen in FIGS. 3, 4 and 5 the fisheye lens assemblyemploys a four (4) lens element, reversed telescope design with the eyeposition or exit pupil located at the small opening of the nose 20. Theconical shape of the nose 20, allows the entire ray bundle entering thesmall opening 21 of the nose 20, which has a very wide angle to reachlens 22. The lenses 22, 28, 36, and 64 (FIG. 4,) are configured anddisposed within the lens assembly such that the angles of the raybundles when the bundles exit from the last lens 64, is consistent witha given thermal imager optical system such as those employed in Mikronmodels 7102, 7200, 7515, and similar thermal cameras. This way a thermalimager can be used in addition to its conventional application, for thepurposes of thermal profiling and hot spot detection in closed-door,high voltage cabinets.

[0026] The following itemized description refers to the referenced itemsin FIGS. 3-5.

[0027] Nose portion 20 (FIG. 5) of the lens housing 13: This has a fewimportant functions. It defines the minimum required hole diameter (forexample, 0.625″ (16 mm)) for the access opening, 92 in the face of thecabinet forming the enclosure. It allows for an easy and precisealignment when used in conjunction with the fisheye view port ring 86(FIGS. 6 and 7) which will be more fully described below. Nose portion20 typically is made from plastic material to insure that an extra levelof electrical insulation exists between the instrument and electricalcabinet door in the unlikely event that a high voltage condition mayexist in the vicinity of the opening 92 in the cabinet face 74. Thediameter of the nose opening 21 in the preferred embodiment is 12 mm.The half angle 23, between the side forming the cone and the opticalaxis 25, in the preferred embodiment is 33° or a total angle of 66°.

[0028] Lens 22 (FIG. 4): The ray bundles emanate from a target, locatedat a distance, from 4″ (10 cm) to 45″ (115 cm), from the nose opening21. They enter the nose opening 21 and are re-directed by lens 22, whichis called an eye lens, towards the other lenses in the assembly. Thematerial of this and all lenses must have a spectral transmissivity inthe infrared range compatible with the infrared transmissioncharacteristics of the particular thermal imager used.

[0029] Retainer 24 (FIG. 3): This is a metallic retaining ring thatholds the eye lens 22 firmly in position and concentric to the systemoptical axis.

[0030] Front Cell 26 (FIG. 3): This portion of the housing 13 isprecision machined from light metal. It houses and provides a seat forthe eye lens 22 and lens 28.

[0031] Lenses 28 & 36 (FIG. 4): The ray bundles from the target whichhave passed through lens 22 are focused onto the combination of lenses28 and 36. The combination of lens 28 and 36 allows for the opticswithin the lens assembly to focus, for different enclosure, interiordistances, by varying the space between them. Lens 28 is stationary andlens 36 moves to allow an optimum image quality for a given interiordistance. They form an intermediate image between lens 36 and lens 64.

[0032] Clamp 30 (FIG. 3): This clamp is made from metal and, togetherwith the retainer 32, holds the lens 36 secure and concentric to thesystem optical axis.

[0033] Retainer 32 (FIG. 3): This retainer is made from metal and incombination with clamp 30 hold the lens 36 in place.

[0034] Lens 36 (FIG. 4): The cooperative relationship between lens 36and 28 allows the optical assembly to focus optimally for differentenclosure, interior distances. Lens 28 is stationary and lens 36 movesrelative thereto.

[0035] Focus Slide 38 (FIG. 3): The focus slide provides a housing andseating for lens 36. It also allows sliding of lens 36, left and rightas viewed in FIG. 3, for optimum focusing. A gentle pressure exerted bya plurality (eight, typically) of springs 56 circumferentially disposedaround its perimeter, provides the necessary force to keep the focusslide 38 in position once the desired focusing is achieved.

[0036] Spacer Tube 40 (FIG. 3): A precision machined metallic part thatguides the focus slide 38 in a concentric manner.

[0037] Scale Tube 44 (FIG. 3): A precision machined metallic part, withthe focusing distance marking 45 engraved in inches and/or metric scale.Four setscrews 46 circumferentially disposed around the perimeter oftube 44, hold the scale tube 44 to actuator nut 50 after an optimumfocusing is achieved for a given, cabinet interior distance.

[0038] Pin 48 (FIG. 3): This pin restricts the motion of focus slide 38to only horizontal movement. It prevents the lens 36 from rotating. Itassists in maintaining the precision of the optical axis.

[0039] Actuator nut 50 (FIG. 3): This is a precision machined metallicpart that holds the guide pin 48 loosely. As the actuator nut 50rotates, it forces the guide pin 48 to slide forward or backward forcingthe focus slide to change the spacing between lens 28 and 36 for optimumimage quality. It also provides a mounting thread to seal retainer 54.

[0040] Seal Retainer 54 (FIG. 3): A precision machined metallic partthat seals the sensitive and exposed parts of the assembly from dust anddirt and also gives a finished look to the assembly.

[0041] Springs 56 (FIG. 3): As noted above, these springs (eight areused in the assembly of FIG. 3) provide a constant, necessary force tourge the focus slide 38 forward, to insure that the spacing between lens28 and 36 will not change, once set, during actual usage of the lensassembly in the field.

[0042] Retainer 58 (FIG. 3): The retainer is a precision machinedmetallic part that forces the spacer 62 against the objective lens 64.

[0043] Rear Cell 60 (FIG. 3): A precision-machined metallic part thathouses and provides a seat for the objective lens 64 and ensures itsconcentricity to the entire optical assembly. In addition, it provides asecure platform for a precision coupling to the front end of a giventhermal imager, optical system.

[0044] Spacer 62 (FIG. 38): A precision machined metallic part thatholds the objective lens 64, in place, concentric to the opticalassembly.

[0045] Lens 64 (FIG. 4): The objective lens 64 takes the intermediateimage produced by lens 22, 28 and 36 and produces near parallel raybundles coming from a desired target and projects these rays into theoptical system of a given thermal imager camera 14 (FIG. 1).

[0046] Setscrews 66 (FIG. 3): A set (four) of dog tail setscrews thatallow the connector 68 to freely rotate on rear cell 60.

[0047] Connector 68 (FIG. 3): This is a precision machined metallicring. It connects the entire fisheye optical assembly firmly andconcentrically to the host thermal imager (camera) optical system. Italso maintains the proper distance between the lens 67 of the camera andthe objective lens 64 of the fisheye optical assembly. The outsidediameter of the rear connector 68 is knurled to provide a firm gripduring attachment of the fisheye assembly to the camera.

[0048] Camera 14 (FIG. 1): The thermal imager camera 14, for exampleMikron's thermal imagers model 7102, 7200 and 7515, includes an opticalsystem which produces a thermal image of the target on a detector focalplane array 72 (FIG. 3). Software internal to the Mikron camerasmentioned above, produces various graphic portrayals of the received,infrared data. For example, a full radiometric thermal image of thedesired target (see FIG. 8) can be immediately viewed through the eyepiece view finder 73 of the camera and/or stored on a digital media forsubsequent use or processing outside of the camera.

[0049] Cement 34 (FIG. 31): A cement such as Locktite® adhesive # 495,or equivalent, is used, as required, for permanent binding of somemetallic parts.

[0050] A lens cap (not shown) protects the fisheye lens during storagefrom dust and dirt settling on optical surfaces.

[0051] Teflon® type tape 42 and 52, with exact thickness, is placed, asrequired, between metallic parts to reduce the friction between movingparts such as between the focus slide 38 and the spacer tube 40.

[0052] For the fisheye lens-camera assembly portion of the invention tobe able to create thermal images of the interior of a high voltageelectrical cabinet 94 so as to locate possible hot spots, an infraredviewing, access opening 92 (FIG. 6) is needed. This opening must allowinspection, but at the same time not be of such size as to degrade theNEMA safety rating of the electrical cabinet. The opening 92 is locatedin the cabinet face 74, at a position, in relation to the electricalpower distribution blocks 96 (see FIG. 7), that optimizes the field ofview for the lens assembly-imaging camera combination. Most high voltageelectrical cabinets used are NEMA 1, 2, 3, 4 or 12 rated. The infraredviewing opening designed for the present invention allows the cabinet toretain a NEMA 4 rating which is the most demanding and meets the moststringent requirements.

[0053] Infrared View Port Alignment Ring 86 (FIG. 6): This part ismachined or cast from metal or plastic and includes a central opening87. The diameter of the opening is slightly larger(0.65 inches, 16.5 mm)than the access opening 92. Its primary function is to provide a nestingplatform for the nose 20 of the fisheye lens assembly to rest and toaxially align the optical axis 25 with the centerline axis of the hole92 already drilled through the electrical cabinet face 74 for inspectionpurposes. The view port ring 86, in combination with the frusto-conicalshape of the nose portion 20 of the housing 13, also providesapproximately 10 degrees of freedom for the fisheye lens assembly torotate, in any direction, in search of hot spots inside of theelectrical cabinet 94 near the perimeter of the field of view. Inaddition, the port includes precision grooves for insertion of, twoo-rings 84, 88,(FIG. 6) on both sides thereof for sealing out dirt andwater, so that the NEMA 4 rating can be met and preserved.

[0054] Cap 90 (FIG. 6): This cap is machined or cast from high strengthplastic. The cap, when secured to the view port ring 86, will seal theinfrared viewing port by compressing the outside o-ring, 88. Thisinsures the integrity of the cabinet NEMA rating before and afterinfrared inspection.

[0055] Ring and Chain Assembly 80, 81, 82 (FIG. 6): The chain-retainingring 81 is made from thin metal either by stamping or laser cutting.Chain 80 is secured to the ring 81 at eyelet 79. Screw 82 at the otherend of the chain is threaded into opening 83 in cap 90. Screws and Lockwashers 76 & 78 (FIG. 6) are needed for installation of the infraredviewing port to the cabinet face 74 via the mounting holes 85 astypically configured and shown in FIG. 6. Chain 80 is of sufficientlength so that when the retaining ring 81 is secured to the cabinetdoor, the retaining ring 81 holds the chain 80 freely, allowingunscrewing of the cap with ease, while retaining the cap chained to theview port assembly. This serves as a constant reminder to inspectionpersonnel that the cap should be screwed in place after completion ofthe monitoring function so as not to breach the NEMA ratingrequirements.

[0056]FIGS. 7 and 7A depict schematically the application of thecombined fisheye lens assembly 12 and thermal imager 70 for use in thethermal imaging of electrical power distribution blocks 96 in theinterior of an enclosure or cabinet 94. In FIG. 7A, the field of view 98for the assembly is shown, for example, as 40° vertically and 53°horizontally, or 66° on the diagonal. The diagonal field of view of 66°stays constant regardless of the focusing distance. The camera-lensassembly can be moved up or down and/or side to side while the nose 20of the assembly is nested in the view port ring 86. This expands thefield of view sufficiently to permit scanning of the interior of theenclosure. The operator can focus more directly on the perimeter areasof the field of view so as to double check for possible lens vignettingerrors.

[0057] Operational Procedure

[0058] The following is a suggested procedure for utilizing the thermalimaging combination of the invention. First-of-all a standard camera 14is selected. All Mikron thermal imagers such as model 7102, 7200 and7515 are acceptable for this measurement. The camera is connected to thefisheye lens assembly 12. The camera is then “set-up”; and, finally, theactual measurements made.

[0059] Camera-Lens Assembly Procedure:

[0060] First, the operator removes any existing lens ring on the imagingcamera. He then secures the fisheye lens assembly 12 to the camerataking extra care to protect the camera's lens mounting threads, so asto avoid stripping the threads.

[0061] The camera 14 should then be adjusted to compensate forattenuation through the wide-angle, lens assembly 12. Thermal imagecameras include this selection ability and internal frimwareautomatically adjusts for attenuation of the lens assembly 12. The scaletube 44 is rotated to set the lens assembly for an average depth of theenclosure, if known.

[0062] The level and sensitivity of the imaging camera is then adjustedaccording to the imager instruction manual. Usually 100° C. is themaximum temperature; while ambient is the minimum.

[0063] Actual Measurement:

[0064]1. The operator first supports the fisheye lens assembly with theleft hand. The right hand is placed in the imager strap. (See FIG. 2)

[0065]2. The lens cone 20 is then inserted flush into the view port ring86.

[0066]3. While viewing through the eyepiece of the thermal imager, theoperator, if required, is directed to move the imager up and down andsideways, to view larger regions inside the cabinet. He adjusts thefocus to sharpen the image, as he does this, at each location, ifrequired.

[0067]4. One possible image available to the operator, as noted above,because of the software built into the Mikron Company's cameras, is aspictured in FIG. 8. As viewed through the camera and as may bereproduced in a photograph or stored on a digital medium, the image at100 is, in fact, a colorized rendition of the temperature profile of thefield of view of the lens assembly for a given axial placement in theview part ring 86. The operator can select various points of interestand identify them on the image, 100, such as points 1, 2, 3, etc. Theinternal software will produce and display the associated temperatures,103. The software can also provide a temperature scale, in color, 104,which allows the operator to more critically evaluate the image 100 inreal time.

[0068] Thermal imaging cameras such as Mikron's model #s 7102, 7250 and7515 store the images and data to PCMC1A cards. This allows subsequentanalysis using a PC. Software is available which allows post imageanalysis. Also, more sophisticated software will permit computerenhancement of areas where distortions may occur, for example, thedistortions attributable to fish-eye lens vignetting.

[0069] Thus it can be seen that the wide angle fisheye lens assembly ofthe invention provides new conveniences, safety, and economy when usedin conjunction with traditional thermal imaging equipment and arelatively small access hole in the cabinet defining the enclosure. Thefisheye lens assembly of the invention has been described for use withthe specific thermal imaging camera of the assignee. It is to beunderstood that the fisheye lens assembly may be reconfigured foroperation with other thermal imagers and other applications withoutdeviating from the basic concept of the present invention.

[0070] While the present invention has been disclosed in connection witha preferred embodiment shown in detail, various modifications andimprovements will become readily apparent to those skilled in the art.

[0071] So for example, whereas the preferred embodiment discloses theuse of a separate fish-eye lens assembly taken together with a standard,available thermal imager, to accomplish the purposes of the invention,the breadth of the invention envisions the inclusion of the fish-eyelens assembly within an overall housing which includes the thermalimaging aspects of a standard camera. A reduction in the number oflenses of course would be a consequence of this combination leading to areduction in the expense of the unit.

[0072] Further, even though a series of lenses are employed in thepreferred embodiment of the fish-eye lens assembly, developments inoptics suggest the use of aspherical lenses to compensate fordistortions that presently require the use of a series of lenses toremedy. As such, a single wide-angle lens of appropriate design, shouldbe able to accomplish the purposes of the series of lenses.

[0073] Accordingly, the spirit and scope of the present invention is tobe limited only by the following claims.

What is claimed is:
 1. In combination, an assembly for the thermalprofiling of heat generating elements within an enclosure encompassed bya cabinet, the cabinet having a first face, the heat generating elementsdisposed a fixed distance, within a range, from said first face, thecombination comprising: (a) a lens assembly, said lens assembly of thefish-eye configuration, including (i) a housing; (ii) a series ofinfrared transmitting optical lenses mounted within said housing;  saidhousing configured to have a co-axially aligned open front end and openrear end, said open front end being substantially smaller in relation tosaid open rear end; (b) a thermal imaging camera,  each of said lensesin said series of infrared transmitting optical lenses being compatiblewith the spectral transmissivity of said thermal imaging camera; (c)means for connecting said open rear end of said housing to said thermalimaging camera; and, (d) an access opening formed in the face of thecabinet, said access opening having a predetermined relationship to theheat generating elements, so that when said means for connecting isactivated to form a combination of said thermal imaging camera and saidlens assembly, an operator may position said open front end of saidhousing immediately adjacent said access opening, thereby enabling saidoperator to view infrared radiation rays originating from the heatgenerating elements.
 2. The combination according to claim 1 wherein oneof said lenses in said series of lenses is a wide angle, objective lens.3. The combination according to claim 2 wherein said wide angle,objective lens has an approximately 66° diagonally wide angle.
 4. Thecombination according to claim 2 wherein said thermal imaging camera isselected from a group consisting of Mikron Instrument Company, Inc.'smodel no. 7102, model no. 7200, or model no.
 7515. 5. The combinationaccording to claim 1 wherein the opening of said open front end of saidhousing is approximately 12 mm in diameter.
 6. The combination accordingto claim 1 wherein said open front end of said housing has afrusto-conical shape tapering downward to an opening of said open frontend.
 7. The combination according to claim 6 wherein said opening insaid open front end is approximately 12 mm in diameter.
 8. Thecombination according to claim 6, further comprising an infrared viewport fixedly secured to the face of the cabinet, said infrared view porthaving an opening, said port opening being concentrically aligned withand positioned about said access opening, said infrared view portadapted and configured to form a nesting platform for said open frontend of said housing, thereby providing said open front end of saidhousing with approximately 10° of rotation in any direction for viewingthe heat generating elements within the enclosure.
 9. The combinationaccording to claim 7 further comprising means for sealing closed saidaccess opening when said access opening is not in use.
 10. Thecombination according to claim 8 wherein the cabinet has a pre-specifiedNEMA safety rating before said access opening is formed in the facethereof, the combination further including means for sealing closed saidaccess opening when said access opening is not in use, wherein saidmeans for sealing closed said access opening are adapted, configured andutilized in a cooperative way with said infrared view port to ensurethat the pre-specified NEMA safety rating of the cabinet is maintained.11. The combination according to claim 10, wherein said means forsealing closed said access opening include a cap for sealingly,enclosing said infrared view port.
 12. The combination according toclaim 11, further comprising a ring and chain assembly connected betweenthe cabinet and said cap, whereby the operator is reminded to re-securesaid cap on said infrared view port after using.
 13. The combinationaccording to claim 1 wherein said access opening has a diameter equal to0.625 inches (16 mm) nominally.
 14. The combination according to claim 7wherein said access opening has a diameter equal to 0.625 inches (16 mm)nominally.
 15. The combination according to claim 8 wherein said accessopening has a diameter equal to 0.625 inches (16 mm) nominally.
 16. Thecombination according to claim 10 wherein said access opening has adiameter equal to 0.625 inches (16 mm) nominally.
 17. A new use forstandard thermal imaging cameras to enable the thermal profiling of heatgenerating elements within an enclosure encompassed by a cabinet, thecabinet having a first face, the heat generating elements disposed afixed distance, within a range, from said first face, comprising thesteps of: (a) selecting a lens assembly, said lens assembly of thefish-eye configuration, including (i) a housing; (ii) a series ofinfrared transmitting optical lenses mounted within said housing;  saidhousing configured to have a co-axially aligned open front end and openrear end, said open front end being substantially smaller in relation tosaid open rear end; (b) selecting a standard thermal imaging camera, each of said lenses in said series of infrared transmitting opticallenses being compatible with the spectral transmissibility of saidthermal imaging camera; (c) connecting said open rear end of saidhousing to said thermal imaging camera; and, (d) forming an accessopening in and through the face of the cabinet, said access openinghaving a predetermined relationship to the heat generating elements, sothat after step (c) is performed, an operator may then position saidopen front end of said housing immediately adjacent said access opening,thereby enabling said operator to view infrared radiation raysoriginating from the heat generating elements when the camera isenergized.
 18. The new use according to claim 17 further including thestep of selecting said standard thermal imaging camera from a groupconsisting of Mikron Instrument Company, Inc.'s model no. 7102, modelno. 7200, or model no.
 7515. 19. The new use according to claim 17wherein said step of selecting a lens assembly further includesselecting a wide angle objective lens.
 20. The new use according toclaim 19 further comprising the step of selecting a wide angle objectivelens having an approximately 66° diagonally wide angle.
 21. The new useaccording to claim 17 further including the step of affixing an infraredview port to the face of the cabinet, said infrared view port having anopening, said port opening being concentrically aligned with andpositioned about said access opening, said infrared view port adaptedand configured to form a nesting platform for said open front end ofsaid housing, thereby providing said open front end of said housing withapproximately 10° of rotation in any direction for viewing the heatgenerating elements within the enclosure.
 22. The new use according toclaim 21 further including the step of providing a cap for sealing saidinfrared view port when said infrared view port is not in use.
 23. Thenew use according to claim 22 further including the step of affixing aring and chain assembly to said cap and the cabinet face.
 24. Incombination, an assembly for the thermal profiling of heat generatingelements within an enclosure encompassed by a cabinet, the cabinethaving a first face, the heat generating elements disposed a fixeddistance, within a range, from said first face, infrared radiation raysemanating from the heat generating elements, the combination comprising:(a) a sub-assembly including (i) a nose piece; (ii) a lens assembly,including at least one infrared transmitting optical lens, mounted infixed predetermined spatial relationship to said nose piece, said lensassembly having a first optical axis and including a ray front surface,said nosepiece having a second optical axis, said nose piece configuredto have a co-axially aligned open front end and open rear end about saidsecond optical axis, said open front end being substantially smaller inrelation to said open rear end, said first optical axis coaxiallyaligned with said second optical axis, (b) an access opening formedthrough the face of the cabinet, said access opening disposed about acenterline axis, said access opening having a predetermined relationshipto the heat generating elements, a portion of the infrared radiationrays passing through said access opening, the spatial relationshipbetween said nose piece and said at least one infrared transmittingoptical lens adapted to produce a wide-angle image output of the portionof the infrared radiation rays passing through said access openingincident at said ray front surface when said open front end is disposedimmediately adjacent said access opening and said second optical axis isco-axially aligned with said centerline axis; and, (c) means co-axiallyaligned with said second optical axis and positioned in spatialrelationship to said lens assembly and adapted to receive, process andimage said wide-angle image output to produce a thermal profile image ofsaid heat generating elements, when said open front end is disposedimmediately adjacent said access opening and said second optical axis isco-axially aligned with said centerline axis.
 25. The combinationaccording to claim 24, further comprising an infrared view port fixedlysecured to the face of the cabinet, said infrared view port having anopening, said port opening being concentrically aligned with saidcenterline axis and positioned about said access opening, said infraredview port adapted and configured to form a nesting platform for saidopen front end of said sub-assembly, thereby providing said open frontend of said sub-assembly with approximately 10° of rotation in anydirection for viewing the heat generating elements within the enclosure.26. The combination according to claim 24 further comprising means forsealing closed said access opening when said access opening is not inuse.
 27. The combination according to claim 25 wherein the cabinet has apre-specified NEMA safety rating before said access opening is formed inthe face thereof, the combination further including means for sealingclosed said access opening when said access opening is not in use,wherein said means for sealing closed said access opening are adapted,configured and utilized in a cooperative way with said infrared viewport to ensure that the pre-specified NEMA safety rating of the cabinetis maintained.
 28. The combination according to claim 24 wherein saidaccess opening has a diameter equal to 0.625 inches (16 mm) nominally.29. The combination according to claim 25 wherein said access openinghas a diameter equal to 0.625 inches (16 mm) nominally.
 30. Thecombination according to claim 27 wherein said access opening has adiameter equal to 0.625 inches (16 mm) nominally.
 31. A method to enablethe thermal profiling of heat generating elements within an enclosureencompassed by a cabinet, the cabinet having a first face, the heatgenerating elements disposed a fixed distance, within a range, from saidfirst face, infrared radiation rays emanating from the heat generatingelements, comprising the steps of: (a) selecting a sub-assembly, saidsub-assembly including, (i) a nosepiece; (ii) a lens assembly, includingat least one infrared transmitting optical lens, mounted in fixedpredetermined spatial relationship to said nose piece, said lensassembly having a first optical axis and including a ray front surface,said nosepiece having a second optical axis, said nose piece configuredto have a co-axially aligned open front end and open rear end about saidsecond optical axis, said open front end being substantially smaller inrelation to said open rear end, said first optical axis coaxiallyaligned with said second optical axis, (b) forming an access opening inand through the face of the cabinet, said access opening disposed abouta centerline axis, said access opening having a predeterminedrelationship to the heat generating elements, a portion of the infraredradiation rays passing through said access opening, the spatialrelationship between said nose piece and said at least one infraredtransmitting optical lens adapted to produce a wide-angle image outputof the portion of the infrared radiation rays passing through saidaccess opening incident at said ray front surface when said open frontend is disposed immediately adjacent said access opening and said secondoptical axis is co-axially aligned with said centerline axis; and, (c)providing means co-axially aligned with said second optical axis andpositioned in spatial relationship to said lens assembly and adapted toreceive, process and image said wide-angle image output to produce athermal profile image of said heat generating elements, when said openfront end is disposed immediately adjacent said access opening and saidsecond optical axis is co-axially aligned with said centerline axis. 32.The method according to claim 31 further including the step of affixingan infrared view port to the face of the cabinet, said infrared viewport having an opening, said port opening being concentrically alignedwith and positioned about said centerline axis of said access opening,said infrared view port adapted and configured to form a nestingplatform for said open front end of said sub-assembly, thereby providingsaid open front end of said sub-assembly with approximately 10° ofrotation in any direction for viewing the heat generating elementswithin the enclosure.
 33. The method according to claim 32 furtherincluding the step of providing a cap for sealing said infrared viewport when said infrared view port is not in use.
 34. The methodaccording to claim 33 further including the step of affixing a ring andchain assembly to said cap and the cabinet face.